2.
There are points D, E and F on the sides BC, CA and AB of triangle ABC, and the inscribed circles of triangles AEF, BFD and CDE are all circumscribed with the inscribed circle of triangle EDF. Set the tangent point on DE. EF.FD are P, Q and R respectively, and it is proved that CP, AQ and BR***.
The flight destination of photon rocket is the center of the Milky Way. It is known that the distance from the center of the Milky Way to the Earth is r = 3.4 * 10 4 light years. In the first half of the rocket, the acceleration is a' = 10m/s 2 (relative to the static system of the rocket), and it decelerates at the same acceleration in the second half. When the rocket reaches its destination, its static mass is m'.
There are three people staying in the hotel. The total room rate is 30 yuan, and the delivery fee per person is 10 yuan.
The hotel gave a discount, and the boss returned to 5 yuan.
The man returned 1 yuan to each tenant, and the man himself didn't know about 2 yuan.
In fact, each tenant paid 9 yuan, March 27, 2 yuan, was kept in the dark by the man, has been 29 yuan. Where did the remaining 1 yuan go?
In 2022, the enrollment charter of Xinjiang Vocational College of Science and Technology has been published, which m